1. Field of the Invention
The invention relates to an arrangement for electrically contacting an electrical component, in particular, a capacitor for a power converter of a rail vehicle. The electrical component has a protruding pin for applying and/or positioning parts of the arrangement in order to produce the electrical contact. The invention further relates to a corresponding method for electrically contacting an electrical component.
2. Description of Related Art
Capacitors have been used for several years to store electrical energy, in particular the braking energy of rail vehicles. The energy stored in the capacitors can be used, in particular, for the next start-up process or acceleration process. Capacitors, however, are also used as filter capacitors in electrical circuits included in power inverters to convert direct current and to operate the traction motors of a rail vehicle. In addition, smoothing capacitors can be used in the circuits for smoothing the direct voltage on the direct voltage side of the power inverter. In these applications in particular, capacitors are frequently combined into assemblies having a plurality of capacitors.
In one usual configuration, the housing of the capacitor is cylindrical and is connected to one of the two electrical potentials of the capacitor or the plurality of the capacitors arranged in the housing. The other potential is connected to a pin-shaped contact on the front of the housing.
The invention relates, in particular, to those types of applications or contacting the capacitors in such applications. However, the invention is also suitable for other electrical components having a protruding pin constructed, in particular, as a pin-shaped contact. The pin in particular serves to apply and/or position parts used for producing an electrical contact.
In particular because the material has very good conductivity and parts are relatively easy to manufacture from the material, copper material is frequently used for electrical contacts. The term copper material describes a material with a very high proportion (e.g., more than 50%) of copper or that is even virtually pure copper.
In particular for the aforementioned applications for rail vehicles, the capacitors may be charged and discharged at high currents of, for example, more than 100 A. For producing an electrical contact, tabs made of copper sheet are usually used. One possible embodiment of the design of the end region of one such copper sheet provides a slot extending from the free end into the end region where the two blades created in this manner accommodate the contact pin of the electrical component between them so that the contact pin is located in the slot. For example, the end region of the contact sheet can then be screwed tight by means of a nut screwed onto the contact pin equipped with an external thread. However, a disadvantage of this is that the copper flows, i.e., it changes shape, under mechanical pressure over time. For this reason, the two blades may migrate outward impairing the electrical contact with the contact pin. There exists the risk of a loss of contact material.
If the copper tab, i.e., the copper sheet end region, has a hole through which the contact pin of the component extends, migration of the material can be prevented in one direction. However, such copper tabs are difficult to assemble. They cannot be moved toward the contact pin from the side but rather must be placed over the contact pin from above.
It is one object of this invention to specify an arrangement and a method of the type cited at the beginning that permit simple assembly and provide a permanently reliable electrical contact.